Patent GB-532936-A (GB)
Title: Improvements in glass working apparatus
IPC: C03B9/28
Filed: 1939-07-31
Abstract: 532,936. Making hollow glassware. CORNING GLASS WORKS. July 31, 1939, No. 4710/40. Convention date, Aug. 12, 1938. Divided out of 532,888. [Class 56] A machine for forming blown hollow glassware such as electric lamp bulbs, tumblers, or lamp chimneys, comprises a chain of orifice plates which move continuously and receive charges of molten glass, devices for blowing the charges in moulds and mechanism for rotating the orifice plates about their own axial centres in order to rotate the glass articles in the moulds. The orifice plates 100, Fig. 7, are carried by blowhead links 291 which alternate with drive links 292 in an endless chain passing horizontally around two turrets that rotate on vertical columns. A stream of glass from a feeder is cut into charges, and the charges are shaped and delivered to the orifice plates as described in Specifications 532,888, and 532,935. Each blowhead link 291 carries a yoked member 308, the lower part of which is formed with guides 314 in which an orifice plate is free to slide. The member 308 has an extension 309, Fig. 8, which is journalled in the link and is splined into a gear wheel 316 that engages another gear wheel 318. The wheel 318 is driven through a friction washer 324 by a pinion 325 which is permanently in mesh with an endless rack secured to the frame of the machine. Thus the member 308 and the orifice plate are rotated about a vertical axis, but this rotation is prevented by a cam-operated stop 341 except during those periods when the orifice in the plate 100 is axially aligned with a blowhead 343. The blowhead 343 is secured to the lower end of a hollow spindle 344, the upper end of which has a shoe 306 that is pressed resiliently against the underside of an elongated box or chamber connected with a source of compressed air. The underside is formed with apertures through which air passes to the spindle 344 and to the blowhead 343. Escape of air from the apertures not covered by the shoes 306 is prevented by shoes 305, Fig. 7, carried by the drive links 292. The blowhead is moved vertically by cam-operated pivoted arms 368 which engage a collar secured to the upper end of the blowhead spindle. In operation, as each link 291 approaches the loading position, the rotation of the member 308 is prevented by the stop 341, and the plate 100 is moved outwards along its guides 314 by a rotating arm which strikes and slides the plate. After the plate has received a charge of glass, it is moved back to its correct position under the blowhead 343 by another rotating arm, and immediately the blowhead is lowered to press the charge against the rim of the orifice in the plate 100. As the link 291 moves outwards, the shoe 306 engages the underside of the elongated air chamber, so that air is. blown through the blowhead to expand the glass, and at the same time the member 308 and the plate 100 are allowed to rotate. While the glass is expanding, cooling air is blown on to it from a conduit. Next, the expanding parison is enclosed and blown to shape on a mould of the kind described in Specification 532,934. Finally the mould opens, the rotation of the member 308 is stopped, the blowhead rises, and the plate 100 is moved laterally to enable the finished article to be knocked off its moil by a blow from a spring-operated arm. The moil is removed from the plate 100 by a scraper blade.